1. Field of the Invention
The present invention relates to a titanium alloy brake rotor and a manufacturing method therefore. More particularly to a titanium alloy brake rotor in which deformation against thermal stress is reduced and to a manufacturing method for making the brake motor.
2. Description of Background Art
Disk rotors for brakes have been made from iron (cast iron) for providing low cost, reliability in material, and easy manufacturing. The iron brake disk rotor, however, is disadvantageous in that it is heavy in weight and poor in corrosion resistance. As a result, the iron disk rotor largely exerts an adverse effect on fuel consumption, acceleration performance, and inertia force. In addition, corrosion of the disk rotor tends to degrade the braking force and braking mechanism. To solve such a disadvantage, an improved brake disk rotor has been proposed, for example, in Japanese Patent Laid-open Nos. Hei 4-337126 and Hei 4-337127, in which the surface of a rotor main body, which is made from titanium or a titanium alloy, is applied with a double layered coating (underlying layer: hard chromium, surface layer: titanium nitride or titanium carbide).